func()

in controllers/nodelifecycle/node_lifecycle_controller.go [122:189]
50 lines of code
13 McCabe index (conditional complexity)

func (c *CloudNodeLifecycleController) MonitorNodes(ctx context.Context) {
	nodes, err := c.nodeLister.List(labels.Everything())
	if err != nil {
		klog.Errorf("error listing nodes from cache: %s", err)
		return
	}

	for _, node := range nodes {
		// Default NodeReady status to v1.ConditionUnknown
		status := v1.ConditionUnknown
		if _, c := nodeutil.GetNodeCondition(&node.Status, v1.NodeReady); c != nil {
			status = c.Status
		}

		if status == v1.ConditionTrue {
			// if taint exist remove taint
			err = cloudnodeutil.RemoveTaintOffNode(c.kubeClient, node.Name, node, ShutdownTaint)
			if err != nil {
				klog.Errorf("error patching node taints: %v", err)
			}
			continue
		}

		// At this point the node has NotReady status, we need to check if the node has been removed
		// from the cloud provider. If node cannot be found in cloudprovider, then delete the node
		exists, err := ensureNodeExistsByProviderID(ctx, c.cloud, node)
		if err != nil {
			klog.Errorf("error checking if node %s exists: %v", node.Name, err)
			continue
		}

		if !exists {
			// Current node does not exist, we should delete it, its taints do not matter anymore

			klog.V(2).Infof("deleting node since it is no longer present in cloud provider: %s", node.Name)

			ref := &v1.ObjectReference{
				Kind:      "Node",
				Name:      node.Name,
				UID:       types.UID(node.UID),
				Namespace: "",
			}

			c.recorder.Eventf(ref, v1.EventTypeNormal, deleteNodeEvent,
				"Deleting node %s because it does not exist in the cloud provider", node.Name)

			if err := c.kubeClient.CoreV1().Nodes().Delete(ctx, node.Name, metav1.DeleteOptions{}); err != nil {
				klog.Errorf("unable to delete node %q: %v", node.Name, err)
			}
		} else {
			// Node exists. We need to check this to get taint working in similar in all cloudproviders
			// current problem is that shutdown nodes are not working in similar way ie. all cloudproviders
			// does not delete node from kubernetes cluster when instance it is shutdown see issue #46442
			shutdown, err := shutdownInCloudProvider(ctx, c.cloud, node)
			if err != nil {
				klog.Errorf("error checking if node %s is shutdown: %v", node.Name, err)
			}

			if shutdown && err == nil {
				// if node is shutdown add shutdown taint
				err = cloudnodeutil.AddOrUpdateTaintOnNode(c.kubeClient, node.Name, ShutdownTaint)
				if err != nil {
					klog.Errorf("failed to apply shutdown taint to node %s, it may have been deleted.", node.Name)
				}
			}
		}
	}
}